Double-acting radial flow steam turbine



1962 R. o. J. MSLLER ETAL 3,056,263

DOUBLE-ACTING RADIAL FLOW STEAM TURBINE Filed March 23, 1961 INVEN7ORS" Clog/deal [7512 i 1 J 4M2? FFiZuncl 3,056,263 DOUBLE-ACTENG RADIAL FLQW STEAM TURBINE Ragnar 010v Jacob Miiller and Torleit Bjarne Anders Frilund, Finspang, Sweden, assignors to Turbin Aktiebolaget de Lara! Ljungstrom, Finspang, Sweden, a

Swedish corporation Filed Mar. 23, 1961, Ser. No. 97,906 Claims priority, appiiration Sweden Apr. 9, P966 2 Claims. (Cl. 60-73) The present invention relates to a double-acting radial flow steam turbine comprising two blade systems and has for one of its objects the production of a simplified and more eifectively operating structure.

The two blade systems are axially displaced and consist of turbine disks and circular rows of blade rings to which the blade systems steam is supplied from a steam chambet at the side of the turbine where the low-pressure blade system is located and through which the steam ultimately flows and enters the high-pressure system through openings in the turbine disk that is located adjacent to the steam chamber.

The latter blade system is located at the opposite side of the turbine and is sealed from the low-pressure blade system by a labyrinth seal.

The invention is characterised by the fact that an outer turbine disk of the high-pressure system is connected to an intermediate turbine disk of the low-pressure system by means of a ring having apertures and which communicates, through an intermediate superheater by conduit means with openings located radially outside of openings provided in an outer turbine disk of the low-pressure system and serving to supply a flow of admission steam.

A turbine constructed as above described has numerous advantages. Until the present time, double-rotating turbine plants having intermediate superheating facilities have been constructed with at least two separate turbines, as distinguished from the single turbine of the present invention, which results in considerable advantages with respect to the saving of both cost and space. Since hightemperature steam for the high-pressure and low-pressure systems is supplied from the same side of the turbine, the steam chambers will not be subjected to any thermal stresses. Also, since there will be no steam piping excepting outlet pipes at the opposite side of the turbine, space will be saved at that side, allowing both the high-pressure and low-pressure systems to be housed in an axial space equal to that occupied by a conventional radial-flow turbine having a single blade system and steam inlets at both sides. This facilitates the use of a number of like components for both turbine types resulting in considerable saving and other advantages.

It is therefore an object of the invention to provide a turbine constructed as above described and which will have the advantages above mentioned as well as other advantages apparent to those skilled in this art.

With these and other objects to be hereinafter set forth in view, we have devised the arrangement of parts to be described and more particularly pointed out in the claims appended hereto.

In the accompanying drawing, wherein an illustrative embodiment of the invention is disclosed, the FIGURE therein shown discloses in axial section the upper portion of a turbine constructed according to the invention.

The turbine is provided with two blade systems indicated respectively at 1 and 2, and displaced axially and having circular rows of blades. The system generally indicated at 1 is the high-pressure system, while that generally indicated at 2 is the low-pressure system. Two shaft ends are respectively shown at 3 and 4.

The shaft end shown at 3 carries turbine disks shown at 5 and 6, that shown at 5 being an outer disk and forming a part of the high-pressure system, while that shown at 6 is an intermediate disk constituting a part of the lowpressure system. The shaft end shown at 4 carries turbine disks shown at 7 and 8, the disk shown at 7 being the outer turbine disk of the low-pressure system. Seals for preventing steam leakage and for balancing purposes are shown at 9 to 15 inclusive.

The steam is supplied through a pipe conduit 16 and openings 17 in the turbine disk '7 to the high-pressure system located at the opposite side of the structure. The steam flows through this system and through a ring or annulus 18 connecting the turbine disks 5 and 6 and through a conduit 19 to an interstage superheater 26, from which, through a conduit 21 and openings 22 disposed radially outwardly of the openings 17 in the disk '7, the steam is admitted to the low-pressure system, and thence to a discharge box 23.

The seal 23 may be made small in size since it is only required to seal off the pressure drop in the superheater and pipe conduits, this pressure drop being relatively small.

With the construction disclosed, the arrangement is such that the steam is supplied from the same side of the turbine, and as a result the steam chambers will not be subjected to any substantial thermal stresses. With the exception of the outlet pipes at the opposite side of the turbine, steam piping is appreciably reduced and this allows both the high-pressure and low-pressure systems to be conveniently housed in a space substantially equal to that required by a conventional radial flow turbine having a single blade system and steam inlets at both sides.

Having thus described a single embodiment of the invention, it is obvious that the same is not to be restricted thereto, but is broad enough to cover all structures coming within the scope of the annexed claims.

What is claimed is:

1. A double-rotating radial flow steam turbine comprising, two axially-displaced blade systems, one of which is a low-pressure system and the other being a high-pressure system, said systems consisting of turbine disks and circular rows of blade rings to which steam is supplied from a steam chamber at that side of the turbine at which the low-pressure system is located, the steam flowing through and entering the high-pressure system through openings in a turbine disk located adjacent to the steam chamber, the high pressure blade system being located at the opposite side of the turbine, a labyrinth seal sealing of]? the high-pressure system from the low-pressure system, the high-pressure and low-pressure systems each including an outer turbine disk, the low-pressure system including an intermediate turbine disk to which the outer turbine disk of the high pressure system is connected, an apertured ring, an intermediate superheater with which the apertures in the ring are in communication, the outer turbine disk of the low-pressure system having openings connected by the conduit means to the superheater.

2. In a turbine construction of the character described, high and low-pressure blade systems, the high-pressure system including an outer turbine disk and an inner disk, said disks being connected by an apertured ring, conduit means establishing a connection between the apertures in the ring and a superheater, the low-pressure system in cluding an outer turbine disk having openings, and conduit means disposed radially outside of said openings for establishing communication with the superheater.

References Cited in the file of this patent UNITED STATES PATENTS 2,218,957 Moller Oct. 22, 1940 2,613,504 Warren Oct. 14, 1952 FOREIGN PATENTS 89,513 Sweden June 22, 1937 

